How would i create a realistic coat material for a horse model of mine?
I have a similar problem; I need to render a horse in Blender Render for work, and the best thing I've found so far is to add noise to your texture, and then use the noise layer as a bump map. With horses, I've found, having good definition of the muscles on the body really helps a lot.  Alas that's something I'm still working on.